Search results

  1. S

    Green's function for a critically damped oscillator

    Homework Statement Consider critically damped harmonic oscillator, driven by a force F(t) Find the green's function G(t,t') such that x(t) = ∫ dt' G(t,t')F(t') from 0 to T solves the equation of motion with x(0) =0 and x(T) =0 Homework Equations x(t) = ∫ dt' G(t,t')F(t') from 0 to T The...
  2. S

    Calculating the ripple factor from oscilloscope

    Hello fellow physicists! I have a lab about rectifying and filtering circuits and I was asked to calculated the ripple factor using an oscilloscope. I managed to get the ripple waveform shown on the oscilloscope, but the thing is there are so many values to read off I have no idea which to...
  3. S

    Classical mechanics equation of motion

    Homework Statement A point mass m moving along the z axis experiences a time dependent force and a fricitional force. Solve the equation of motion m\ddot{z} = -m\gamma\dot{z} + F(t) to find v(t) = \dot{z}(t) for the initial velocity \dot{z}(0) = v_0 Hint: what is the time derivative of...
  4. S

    Classical mechanics with time dependent force

    Homework Statement A point mass m is exposed to a time dependent force F(t). Determine the position r(t) of the point mass for the initial conditions r(0) = r_{0}and v(0) = v_{0} Homework Equations The Attempt at a Solution \sumF= ma F_{z}(t) - mg = ma a = 1/m F_{z}(t) - g...
  5. S

    Coordinate systems

    Homework Statement For the cartesian, cylindrical, spherical coordinate system, prove that \nabla.\vec{r} = 3 and \nablax\vec{r}=0 Homework Equations For cylindrical coord system, \vec{r} = s\vec{s} + z\vec{z} \nabla = \vec{s} \delta/\deltas +...
  6. S

    Physical pendulum

    Homework Statement http://hyperphysics.phy-astr.gsu.edu/hbase/pendp.html#c2 i'm trying to prove to be Homework Equations Letting d = Lcm now we already know \partial^2\vartheta/\partial t^2 = \alpha = mgdT\vartheta / I I tried integrating the whole equation wrt dt so...
  7. S

    Diffraction - maxima

    Homework Statement Show that the angular locations of the first to fourth secondary maximas are \alpha = a sin \Theta/\Lambda = 1.43030 2.45902 3.47089 4.46641 respectively. a is the slit width = 0.00016m \Lambda wavelength of laser 650nm Homework Equations I(\Theta) = I0...
  8. S

    Steffan-Boltzman Law

    Hi guys, I need help on my concept on the steffan's law. I understand that for a grey body sphere confined within a blackbody spherical shell, the general forumla for the net power radiated from inner sphere should be Prad = kAe(T4-Tsurr4) where k=stefan boltzman's constant However...
  9. S

    Standard deviation in Graviational force, g

    I'm doing a lab report, but I don't need help for it. I just need the standard deviation in g. I need to compute the theoretical value for centripetal force together with its uncertainty for my circular motion experiment. That is, since my mass was measured to be 0.208536kg, standard...
  10. S

    Light reflection angles

    Homework Statement For a beam of light shone on a prism, the reflected beams will give twice the angle of the prism. Homework Equations We know that the angle between the incident ray and the normal = angle between reflected ray and normal The Attempt at a Solution i tried drawing...
  11. S

    Integration to find volume generated

    To find the volume generated by rotating an area bounded by 2 curves f(x) and g(x) around the x-axis we use the formula Int of lower and upper intersections pi( f(x)^2-g(x)^2 ) dx or Int of lower and upper intersections pi (f(x)-g(x))^2 dx...
  12. S

    Percentage Discrepancy

    Homework Statement Hi guys, I need help with percentage discrepancy. Homework Equations I understand that percentage discrepancy is given by |observed value - measured value| / measured value x100% where || is the absolute value. The Attempt at a Solution However, one of my...
  13. S

    Spring balance concept

    Homework Statement This was a concept question my lecturer gave us, and although he tried to explain it thoroughly, I still didn't get it. So I was hoping someone could help me out. There are 2 parts to this question Firstly a spring balance is attached hanging from a celling using a...
  14. S

    Cycloid Particle question

    Homework Statement A particle moves in a plane according to x= Rsin(wt) = wRt y= Rcos(wt) + R where w and R are constants. This curve, called a cycloid, is the path traced out by a point on the rim of a wheel which rolls without slipping along the x-axis. Question: (a) Sketch...
Top